The present invention relates generally to improved water-tight attachment of metallic parts without removal of the corrosion resistance property of coatings associated therewith.
In connection with the attachment of a metal pan to the underside of the metal deck of a ship or the like, currently utilized welding methods which generate heat thereby destroy much of the corrosion resisting property of the paint coating on the deck underside adjacent to the cleave opening location at which a metal pan is attached to the deck. It is therefore an important object of the present invention to provide an attachment process or method, of minimized duration, which will avoid destruction or removal of the corrosion resisting property of paint coatings on marine vessel decks, necessary for protection thereof in seawater environment.
In regard to other environments, the attachment of metallic parts which involve physical interconnection by screw fasteners extending through sealing gaskets between such parts are generally known. Such gaskets are positioned as solid sealants between the parts to perform their exclusive sealing function while accommodating separation of the parts upon removal of the screw fasteners. It is therefore another object of the present invention to provide a sealing gasket which also performs a perrnanent bonding function during attachment between the metallic parts.
In accordance with the present invention, metallic parts, surface coated with a corrosion resisting paint, undergo attachment to each other for use in a corrosion inducing environment, such as a marine vessel in seawater. The attachment process therefore involves use of a gasket for both sealing and permanently bonding the metallic parts to each other without adversely affecting the corrsion resisting property of surface coating paint adjacent to the attachment locations. The gasket is formed from a polymeric composite material having the requisite sealing and bonding properties as well as accommodating relatively rapid solidification from a liquid phase under normal temperature conditions. Such gasket material in the liquid phase is placed in position between the attachment portions of the assembled metallic parts for in-place solidification into a sealant while establishing permanent bonding between the metallic parts without adversely affecting the corrosion resisting property of the surface coating paint, as in the case of welding. Following such in-place solidification of the gasket material, the metallic parts are physically interconnected by lock nut bolting involving extension of screw fasteners through the solidified gasket to provide for an increase in the permanent bonding strength of such gasket.